By default, GNOME’s file manager (Nautilus) relies on the Totem video player and the GStreamer framework. If your thumbnails are missing, it is usually due to missing codecs or a corrupted thumbnail cache. This guide covers how to fix it and switch to ffmpegthumbnailer for better performance.
Note: If your videos are on a network drive, ensure Nautilus is set to show thumbnails for "All Files" in Preferences > Performance, otherwise it will skip remote files.
Phase 1: Codecs & Cache
First, install the necessary plugins to allow GStreamer to decode common formats like MP4 and MKV. After installing, you must clear the existing "fail" cache.
# 1. Install necessary codecs (Ubuntu/Debian)
sudo apt update
sudo apt install ffmpegthumbnailer gstreamer1.0-libav gstreamer1.0-plugins-ugly
# 2. Clear the thumbnail cache and restart Nautilus
rm -rf ~/.cache/thumbnails/*
nautilus -q
Phase 2: Faster Previews with FFmpeg
The default Totem thumbnailer can be slow. Switching to ffmpegthumbnailer provides faster generation and support for more obscure containers.
| Step | Action |
|---|---|
| Disable Totem | Rename /usr/share/thumbnailers/totem.thumbnailer to .bak |
| Create Config | Create /usr/share/thumbnailers/ffmpegthumbnailer.thumbnailer |
| MIME Types | Add video/mp4, video/x-matroska, video/webm, etc. |
Paste the following configuration into your new .thumbnailer file:
[Thumbnailer Entry]
TryExec=ffmpegthumbnailer
Exec=ffmpegthumbnailer -i %i -o %o -s %s -f
MimeType=video/3gpp;video/3gpp2;video/dv;video/isivideo;video/mj2;video/mp2t;video/mp4;video/mpeg;video/ogg;video/quicktime;video/vnd.mpegurl;video/vnd.rn-realvideo;video/vnd.vivo;video/wavelet;video/webm;video/x-anim;video/x-flic;video/x-flv;video/x-javafx;video/x-matroska;video/x-mjpeg;video/x-mng;video/x-msvideo;video/x-ms-wmv;video/x-nsv;video/x-ogm+ogg;video/x-sgi-movie;video/x-theora+ogg;video/x-matroska-3d;video/vnd.avi;
Troubleshooting
Still No Thumbnails?
Nautilus has a file size limit for thumbnailing to prevent system lag on massive files.
The Fix: Go to Files > Preferences > Performance and increase the "Only for files smaller than" value to 4GB or higher.
Manual Cache Reset Command:
# If individual files won't update, force a global refresh:
rm -rf ~/.cache/thumbnails/fail/*
rm -rf ~/.cache/thumbnails/large/*
rm -rf ~/.cache/thumbnails/normal/*
killall nautilus